Apache Cassandra™ 1.2

Tracking counter columns

You can use the sstable2json command to get information about a counter column.

Procedure

  1. Run the counter example presented earlier `that loads data into a counter column and flushes data to disk.
    The counter is initialized to 1.
  2. Run the sstable2json command.
    sudo ./sstable2json 
             /var/lib/cassandra/data/counterks/page_view_counts/counterks-page_view_counts-ib-1-Data.db
    [
    {"key": "7777772e64617461737461782e636f6d","columns": [[
    "home:","",1370187164256000], [
    "home:counter_value","0001000058852cd0cb9311e2940971f75c7d064100000000000000010000000000000001",1370187164256,"c",-9223372036854775808]]}
    ]
  3. Increase the counter column by 2 and flush the data to disk again.
  4. Run the sstable2json command again.
    sudo ./sstable2json
             /var/lib/cassandra/data/counterks/page_view_counts/counterks-page_view_counts-ib-2-Data.db
    [
    {"key": "7777772e64617461737461782e636f6d","columns": [[
    "home:","",1370187315683000], [
    "home:counter_value","0001000058852cd0cb9311e2940971f75c7d064100000000000000010000000000000002",1370187315683,"c",-9223372036854775808]]}
    ]

    -9223372036854775808 is the timestamp of the last delete.

Show/hide